1. Field of the Invention
The present invention relates to automatic discrimination of signals transmitted between an electronic appliance and a peripheral device connected thereto, which may be applied, for example, to a video tape recorder integrated with a camera.
2. Description of the Related Art
A conventional video tape recorder integrated with a camera (hereinafter called a camcorder) is composed of a camera unit and a VTR unit, in which the image of a subject taken by the camera unit is converted into an electric signal, and the signal is subjected to a specified process by the VTR unit, and is later magnetically recorded in a magnetic tape.
A peripheral device such as a printer and a personal computer can be connected to this camcorder through a cable. By connecting the printer thereto, the data supplied from the camcorder can be printed, or by connecting the personal computer thereto, the mode and operation of the camcorder can be set or adjusted.
However, since interface formats of transmitted signals are different depending on the peripheral devices connected to the camcorder through cables, there has been a demand that the camcorder be constituted so that cables of plural interfaces can be connected thereto
In such a conventional camcorder, even if a jack is constituted such that cables of plural interfaces are capable of being connected, when signals of two or more kinds are passed onto a same signal line, an undesired signal flows into the camcorder side, which may cause malfunction thereof.
If the signal line is divided into a plurality of lines depending on the types of signals, the number of the cable increases, and there is an inconvenience that the jack of the camcorder side becomes larger in size.
Or if a signal of a large signal level passes in a signal system of a small signal level, the input system of the signal system of a small signal level becomes an excessive input, and the input element may be broken.
If a different signal is passed to the same jack, it requires a changeover of the control system by discriminating the different signal.
Another inconvenience is that the operation is complicated in order to change over the control system on the basis of the detection result of the signal.